1. Field of the Invention:
The invention concerns a passage through the wall of a reinforced concrete pressure vessel for nuclear reactor installations, in particular, gas cooled nuclear reactor installations. The passage contains a metal liner.
2. Background of the Prior Art:
It is known that during the construction of reinforced concrete pressure vessels a plurality of passages are formed in the pressure vessel walls and lined with armor tubes. The function of such a lining is to insure the gas tightness of such a container wall and to reduce stress peaks in the adjacent orifices. The armor tube is joined in a gas tight manner with the inner liner of the reactor vessel by means of welding. Armor tubes designed in this manner serve to receive structural elements of the reactor such as blowers, steam generators, measuring instruments (thermocouples) and other components required for the operation of the reactor, wherein the internal diameter of the armor tube may attain a value of a few centimeters to several meters. The wall thickness of the armor tube is approximately 5 cm. It is desirable to maintain the small tolerances characterizing the armor tube in the course of its manufacture even after its installation in the wall of the reinforced concrete pressure vessel. It is known that during the setting of the armor tube in concrete, and even for an extended period after the completion of the wall, forces are acting in the wall. These forces lead to the deformation or undesirable alteration of the armor tubes. Over the entire life of the vessel, the tubes are subjected to a constant process of change, wherein the magnitude of the change depends on the state of the operation and the life of the installation. Essentially, it is not possible to coordinate or to affect the deformations as they occur. It is necessary to correct any damage that has taken place prior to the installation in the armor tubes of the components for which they are intended. This operation involves a considerable technical effort and financial expenditure and must either be repeated often, depending on the history of the installation, or in the case of a single fitting, does not represent an optimum solution.